An aggregate is a collection of one or two plexes and it supports RAID-level mirroring. If the aggregate is un-mirrored, it contains a single plex. If the SyncMirror feature is licensed and enabled, a second plex can be added to any aggregate, which serves as a RAID-level mirror for the first plex in the aggregate.
aggr create <aggr_name>
[-m] –r <raid_size> –t <raid_type> <total # disks>
snap reserve –A
snap sched –A <aggr_name>